Expandable introducer sheath for medical device

Abstract

Expandable introducer sheaths and associated laser cut frames for the insertion of a medical device into a blood vessel. In some examples, an expandable sheath may have a frame including a plurality of radial expansion bands and a plurality of connecting bridges for connecting adjacent radial expansion bands. The radial expansion bands are configured to accommodate radial expansion and the plurality of connecting bridges are configured to be longitudinally expandable and to impart column strength as a medical device (e.g., an intracardiac heart pump) is passed through the sheath, such as during insertion or removal of the medical device.

1 . An expandable sheath comprising:
 a tubular frame extending along a longitudinal axis from a proximal end to distal end, the tubular frame comprising:   a plurality of radial expansion bands, each radial expansion band at least partially extending around a circumference of the tubular frame, and   a plurality of connecting bridges, wherein each connecting bridge couples a portion of one radial expansion band to a portion of an adjacent radial expansion band, wherein the radial expansion bands and connecting bridges are formed by laser cutting the tubular frame; and   a coating formed over at least an exterior of the tubular frame.   
     
     
         2 . The expandable sheath of  claim 1 , wherein the plurality of radial expansion bands and the plurality of connecting bridges alternate along one of the longitudinal axis of the tubular frame or the circumference of the frame. 
     
     
         3 . The expandable sheath of  claim 1 , wherein each radial expansion band comprises a plurality of band segments that define a zig-zag pattern around the circumference of the tubular frame. 
     
     
         4 . The expandable sheath of  claim 1 , wherein each radial expansion band extends around the circumference of the tubular frame substantially perpendicularly to the longitudinal axis. 
     
     
         5 . The expandable sheath of  claim 1 , wherein each radial expansion band extends around the circumference of the tubular frame obliquely with respect to the longitudinal axis. 
     
     
         6 . The expandable sheath of  claim 1 , wherein each radial expansion band comprises a continuous band strut that is continuous within the radial expansion band. 
     
     
         7 . The expandable sheath of  claim 1 , wherein each radial expansion band includes at least two discontinuous portions, and wherein the discontinuous portions are connected by at least one connection bridge. 
     
     
         8 . The expandable sheath of  claim 1 , wherein each connecting bridge comprises portions configured to interfere with one another when the tubular frame is exposed to a compressive force at least partially along the longitudinal axis. 
     
     
         9 . The expandable sheath of  claim 1 , wherein each of the radial expansion bands extends around the entire circumference of the tubular frame.